Split bowl vs Non split bowl

[farmo83]

So whats the difference between the two (minus the one letter after the J)? What are the performance differences ? Just curious

 

[cakemoto]

for one on a non-split bowl you can bolt any thing up.

 

[farmo83]

You mean a place divereter or a Jetovator ?

 

[Just Electric]

You mean a place divereter or a Jetovator ?

droop straight droop snoots and wedges etc etc .depending on what type of boating and performance gains and hull designs its up to you.if your happy with the way your boat handles and drives then leave it.but its a boat and we all know the story we just cant leave well enough alone.if your going for more performance you just answered you own question

 

[IRRebel]

Here's two pics to help illustrate the difference.

First is a JB bowl, with a wedge installed, no diverter, droop or other accessory. This is pretty much the same as the JG or JF bowl.

Second is a JC Bowl. Same as the JE for all intents and purposes here.

A few schools of thought here, and Tom, correct me if I understand this wrong, but this is my basic understanding of it.

All Berk bowls are interchangeable with all Berk pumps, as far as I know.

The JC bowl is by far the most common. There are many who beleive, and maybe it's true, I have no way of testing, that the JC bowl design outflows all the rest. BUT, you lose a lot of tuneability with it, and short of using a diverter, you have no way of controlling the vertical angle of attack, what I call the Y axis, of planing out a boat.

Then comes the Split bowl, which I understand was designed mostly for race boats so they would have the most finite tuneability possible with them, which would overcome any flow differences, if there are any. Last thing a racer needs to deal with is YET another thing to adjust constantly, like a diverter. Kindof like dialing in a Nascar car with wedges, track bars, etc, same things can be done on a split bowl. Droop snoots, extensions, wedges, all sorts of stuff. Diverters are the same for all of them save the JE and JF.

As far as the pump itself is concerned, they are pretty much identical, with the exception of the JE and JF pumps that have the intake integral with the pump housing. All others have a separate intake that the pump bolts to. Pros and cons either way there as well, and a matter I think Tom had best answer. I have both, and from seat of the pants on lake boats, all perform VERY well.

For nearly all of us, a non split bowl like a JC or JE with a diverter is more than adequate. There are exceptions and they mostly deal with former race hulls, or those looking for max roost, or (dare I say it) bad equipment or mis-matched equipment, IMHO.

Hope this helps.

Ray

 

[Flat Broke]

Here's two pics to help illustrate the difference.

First is a JB bowl, with a wedge installed, no diverter, droop or other accessory. This is pretty much the same as the JG or JF bowl.

Second is a JC Bowl. Same as the JE for all intents and purposes here.

A few schools of thought here, and Tom, correct me if I understand this wrong, but this is my basic understanding of it.

All Berk bowls are interchangeable with all Berk pumps, as far as I know.

The JC bowl is by far the most common. There are many who beleive, and maybe it's true, I have no way of testing, that the JC bowl design outflows all the rest. BUT, you lose a lot of tuneability with it, and short of using a diverter, you have no way of controlling the vertical angle of attack, what I call the Y axis, of planing out a boat.

Then comes the Split bowl, which I understand was designed mostly for race boats so they would have the most finite tuneability possible with them, which would overcome any flow differences, if there are any. Last thing a racer needs to deal with is YET another thing to adjust constantly, like a diverter. Kindof like dialing in a Nascar car with wedges, track bars, etc, same things can be done on a split bowl. Droop snoots, extensions, wedges, all sorts of stuff. Diverters are the same for all of them save the JE and JF.

As far as the pump itself is concerned, they are pretty much identical, with the exception of the JE and JF pumps that have the intake integral with the pump housing. All others have a separate intake that the pump bolts to. Pros and cons either way there as well, and a matter I think Tom had best answer. I have both, and from seat of the pants on lake boats, all perform VERY well.

For nearly all of us, a non split bowl like a JC or JE with a diverter is more than adequate. There are exceptions and they mostly deal with former race hulls, or those looking for max roost, or (dare I say it) bad equipment or mis-matched equipment, IMHO.

Hope this helps.

Ray

Pretty good explanation. Just a point of clarification though. It is not that a C bowl will flow more water than it's slipt configuration counterparts; only that the vanes in the bowl are longer. This allows the discharge to expend less energy in a radial fashion, and more along the actual thrust line. The idea being that since it is the "equal and opposite" reaction part of physics that allows a jet drive to move a boat, any energy spent pushing thrust any direction besides behind the boat is wasting energy.

It's not that the discharge from a C is so much straighter than a spit bowl setup that you're going to feel it or anything like that. It's just one of those tiny little things that when taken into consideration with tons of other tiny little things, that starts to add up to a measurable gain in race boats.

Hope that helps,
Chris

 

[Nordie]

I was going to respond with a similar answer but nevermind everything is already there with your question...honestly i have had both types of bowls and would rather have the split bowl hands down....why? because i want to be able to run an adapter or snoot or droop...or wedges for sexy roosters!

 

[jetboatperformance]

Pretty good explanation. Just a point of clarification though. It is not that a C bowl will flow more water than it's slipt configuration counterparts; only that the vanes in the bowl are longer. This allows the discharge to expend less energy in a radial fashion, and more along the actual thrust line. The idea being that since it is the "equal and opposite" reaction part of physics that allows a jet drive to move a boat, any energy spent pushing thrust any direction besides behind the boat is wasting energy.

It's not that the discharge from a C is so much straighter than a spit bowl setup that you're going to feel it or anything like that. It's just one of those tiny little things that when taken into consideration with tons of other tiny little things, that starts to add up to a measurable gain in race boats.

Hope that helps,
Chris

This is good info/explanation above , when we build/modify the "Cs" (pic) we dont simply chop the bowl off but rather mill and preserve that " longer staightening area" Althought not tested with "documented and provative results" the general concensus is that the modified bowls work better. Unfortunatlely they (G's and C's) are still basically stock Berkely bowls with stock castings and "stock wall thickness" and do have thier strength and HP limitations . I am currently running one on my Blown Mach 1 Jet Tom
http://www.jetboatperformance.biz/catpage/12_jc_split_bowl.html

 

[Devilman]

I was told by Jack at MPD little while back that other than the fact of being able to take advantage of any bolt ons like a droop or wedges, etc. on the average lake boat the difference in performance between a split bowl and a non split bowl would be minimal at best.

I already had a diverter, my situation was wanting to try a droop snoot to see if it helped my boat any. I'm not 100% sure on all aspects of the droop, one is lowering the thrustline, helping the boat to air out/run dryer, or something to that effect? There are others that could explain the workings of a droop better than I. Main thing was just wanting to experiment with my boat & was in the position to do it, so I borrowed a G/split bowl & droop from a friend, ran it & gained 4 mph. So I bought my own. I have yet to experiment with the addition of any wedges...

Thing is, not all boats will respond to those kind of hardware changes the same way. With a split bowl, you are able to do this, with a one piece/non-split bowl, you are not. Hope that makes sense...

 

[HOSS]

I was told by Greg (owner of GS Marine) that my hull will respond badly due to chine walk with a droop. On the other end of the rock Ronnie Sporl told me to run one. I think with the added weight of a diesel the droop would be benificial. `75 Southwind.

 

[TeamHawaiin]

This is some good info. I have wondered if removing the droop snoot from my pump to change the thrust centerline.....if that will help in calming down the porpoising effect on my 17' Hawaiian. I know short jets will porpoise and I have trim tams to counteract but I still have to power through it between 30 and 40 mph. I have to cruise less than 30 or more than 40. I have two 80 lb bags of sand way up in the bow but my idea is to point the bow down with changing the thrust line. Am I on the right track? Here is a pic of the pump.



Oh by the way its a Dominator 12 J with "B" cut impellor, setback with ride plate.


Maybe the boat doesn't like me and it's trying to buck me out

 

[HOSS]

17 feet? damn, u must be running on rails at WOT! :skull